Tyler's 2011.5 Jerez Black E90 Slicktop Daily

[Tbonem3]

Few more odds and ends before I opened up the muffler.

Noticed the rear emblem /// was faded. The price for a new stupid little plastic emblem is so ridiculous, I balked and sought another option. I found some vinyl stickers on ebay for pretty cheap ($10 for 2 iirc - they have E46 size too)




Annual oil/filter & air filter change



I also polished and re-coated the E88s. I've had them now for over 2 years, and they were getting dull.




I used a variety of attachments to reach everything. Griot's BOSS cream for the painted centers and Mother's MAG polish for the rims.



Thoroughly cleaned and prepped for ceramic coating






And a little video showing off both the freshly corrected/coated Jerez paint and the E88s:

https://www.youtube.com/shorts/F7_qyA7GQo0

[MTiz]

Two questions on the stickers, are E9x and E46 badges the same size? And what about F8x? I think I found the listing you bought and I want to replace both my cars M badge stickers but I believe the F80's is bigger.

[Tbonem3]

Two questions on the stickers, are E9x and E46 badges the same size? And what about F8x? I think I found the listing you bought and I want to replace both my cars M badge stickers but I believe the F80's is bigger.

No, the e9x emblem is tiny! But the ebay listing I found had different options.

https://www.ebay.com/sch/i.html?item=156185575862&rt=nc&_trksid=p4429486.m3561.l170197&_ssn=dougn-8

[Tbonem3]

Alright so now I'm documenting what I did to the stock muffler. When you have the factory primary cats on the S65, you can pretty muich do whatever you want muffler-wise and it'll sound great and not too raspy/loud, so the 4 pipe mod was great, but now with test pipes (deleted cats), I need to be careful to not do too much modifying.

Here's what it looks like inside the muffler:



Though welding is a better method, I decided to accomplish my modification with exhaust "repair" wrap. It made the whole job easier and quicker, and most importantly, it allowed me to play with the amount of coveraged to get the desired result (volume/rasp). The main concern now is how long does the wrap stay in place, but so far so good.

First step is to open the muffler up. Some choose to remove a lot of the "shell," but I decided to simply cut "windows" into the 2 sections so that I could close them, test the volume/rasp levels to see if I was happy before welding it shut. Ended up being a great decision as I needed several tries to reach the "right" amount.







So as I had mentioned, I started with a "2 pipe" mod which is where you wrap the 2 fully perforated pipes (I also cut a window into the other side - it's symmetrical, just mirrored)




I used a MAP gas torch to heat the steel before bending it back for 2 reasons - so that the metal doesn't crack and so that it doesn't retain its "spring memory" as I want it to lay closed down as much as possible (I used foil tape to seal it).





Other side:



But it was very raspy and loud. to me, it basically sounded like my older 4 pipe muffler sounded - pretty much wide open. Very loud and harsh and drone-y. So I knew I needed to remove some of the wrap and step it down from a "2 pipe" mod to a 1.5 or even a 1 (2 halves).
I was worried about simply wrapping 1 perforated pipe and leaving one open in order to reach "1 pipe" due to possible having the sound be one dimensional? Not sure, but I think it was wise to still treat each side of the muffler equally in order to get the most dynamic sound.

So I opened the windows back up and removed some of the wrap. I first tried about 3/4s of it wrapped for a "1.5 mod," but still it was too raspy. The volume was good, but the rasp was a bit silly still even with adding another pair of resonators into the X pipe. I was a little confused here; didn't think a 1.5 mod should be so raspy still, but I kept trying to reach a happy medium between volume and rasp.

It took 4 tries, but finally, I was happy after removing basically half of the wrapping, resulting in about 60% of each perforated pipe covered. So a "1 pipe" or I guess a "1.25 pipe mod" :P



^ .75 wrapped then about 60% wrapped v




The end result is pretty darned good. I say it's like a eisennman race "lite". Loud enough to be satisfied at WOT, and the crisp downshifts (like a rifle) scare bystanders, but under normal throttle, it's very stock like. There's definitely an up-tick in rasp, I just couldn't get it to go away, but this is an acceptable level. I like rasp, but with the S65, it's brutal. So this mild amount is good. There is definitely a "drone-y" quality to the sound overall, but I kind of like that. It's not the drone most of us know that's very bassy esp in lower rpms like driving the freeway. This is more of a tonal quality. It's pretty exotic and rowdy and nasty so I'm very happy and it cost like $20.

Now it's time to weld the "windows shut." before closing the windows, I did add in final pairs of metal "zip ties" just in hopes of helping the wrap not come undone over the years.

[Tbonem3]

Some of this is a bit out of chronological order. While figuring out the muffler, I was pretty sure I wanted another pair of resonators added to my X pipe with test pipes. Before I got close to done with the right amount of muffler modification, I knew I needed to get the X pipe finished.

Here's a shot of the resonators again that I found. 2.5" piping, 4" length and a 3.5" body, so not too much bigger than the stock primary cats.



So next I had to mock it all up so I could take measurements in order to recreate the X pipe






Ok, so it was easy to get the dimensions to line up, esp fore and aft, but the tricky part would be getting the ends of the pipe close enough. There's a little wiggle room in the pipes slipping into each other. There's also a natural "spring" to steel, so I knew I just needed it close enough, not absolutely perfect to the millimeter. I figured I could hold the ends together in the desired dimension/distance while the welder lays down some tack welds to hold it. I didn't feel like making an elaborate jig for this.



Got it up on stands at my welder a few streets over (an old friend of my dad's; been welding and machining aircraft parts for 40 years)

Decided to weld the new resonators to the X pipe first. There was a slight discrepancy in the OD of the X pipe and the ID of the resonator which ended up being great as I could "clock" the angle of the resonator inwards with a mallet and it would stay well enough in place while the welder finished one end of it.



Now the other side, where the test pipes were being inserted had a larger discrepancy (TMS test pipes are under 2.5" OD). But once again, I got lucky! This discrepancy really allowed me to angle the test pipes inward to reach the desired dimension of width between the ends where the meet the headers.

However, with a larger gap, that makes welding trickier. In order to help things, I was actually able to cut off the TMS supplied clamps and repurpose them into shims:




Alright, well it worked out great! I was able to get it within 1/8" distance from stock X pipe where they connect to headers. The install was easy, it lined up well, so that was nice. Breaking the welds and re-doing it would not be fun.

Ok so now that they were in, and I could finalize my muffler modifying to reach desired volume/tone, I brought the muffler back to him to seal it up:






Then I wanted to polish it again for a final time, but used a car paint polish with sio2 for ceramic coating prep, then used left over ceramic coating from Gyeon.



All done!



And a little video. Hopefully I can get more, esp out side of the vehicle. But as I said in the last post - it's a nice motorsport sound that's raspy but not overwhelming. It's pretty damn loud at WOT, but surprisingly quiet at moderate throttle, and stock like at low throttle. Overall, very very happy with the cost/sound/looks.

https://www.youtube.com/shorts/bcF7ZTDTJo0

[0-60motorsports]

Sounds amazing. Any plans to do a dyno?

[Tbonem3]

Thanks. No, don't need to see how weak the s65 is

Feels great and the car hustles, so I'm happy.